The invention relates to connectors for cables, to cables including such connectors and to systems having cable interconnects.
In a system having cable interconnects, the identification of local and remote cable connectivity is important for configuration and diagnosis of the cable-based interconnect system. This can include the determination of whether a cable is connected locally, whether it is connected at the remote end or ends (remote end for a single cable or remote ends for a split- or multi-link cable) and where the remote end(s) is (are) connected.
For example, with standard InfiniBand cables, the above issues can only be resolved if the link is able to train, and thereby to allow in-band packet traffic between the associated end-points. Hence, if the link is not able to train, then all the states associated with all the above aspects are in principle un-defined.
In order to address this, various techniques for local cable/connector presence detection, cable connectors with electrically readable FRUID information (i.e., serial-number etc.), combined with side-band and/or out-of-band communication can be implemented. However, even if these techniques are applied, it is still an issue that establishing the relevant state and connectivity information requires an active, “intelligent” entity (e.g., some kind of basic service processor with relevant firmware) associated with all the end points to which the cable is connected. Hence, inherently, this also implies that the end-points must be operating in at least a minimal power mode.
In some cases, it may not be possible to include an intelligent entity in the end-point design (e.g., a line-card implementation with no “side-band” access from any chassis/system service processor to the cable-connectors on the line-card, or an un-intelligent repeater module used to connect two individual cables together). In such cases, none of the desired information would be available until the link(s) associated with the cable connectors had been made operational and/or it might not be possible to determine the complete physical connectivity information.
Accordingly, the invention has been made, at least in part, in consideration of problems and drawbacks of conventional systems.